I like to switch back and forth between 24fps and 60 on the same tape. I've never tried but I think someone said I would have a capture issue if I tried to download video to my computer that goes back and forth between frame rates. I just saw that Avid updated it's software and wondered if this might solve my issue:

Mix and match capabilities let customers use media sources of different frame rates and resolutions (SD and HD) in the same timeline, eliminating external transcoding and time-consuming frame-rate conversions.

They don't advise you to do that since you may have drop outs while capturing. I did it and nothing happened. Doesn't mean it won't. BTW, don't forget regardless of the frame rate, the video is recorded as 1080/60i. If you are using 24p mode it is still recorded as 60i with pulldown. So when you are capturing the video, all of it is captured as 60i and there is no switching between frame rates.

As for the Avid update, it has nothing to do with capturing but working with the footage after capture. And to have a 24p footage you first need to remove the pulldown after capture.

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